Reporting Services :: Timespan - Display Time Difference Between Admission And Discharge Date

I am trying to display time difference between an Admission Date and a Discharge date as follows:

Admission Date:8/26/2015 6:59pm
Discharge Date:9/1/2015 6:49pm
Time Display 5D 23H

I used the following expression but came up with an error

Not sure what I am doing wrong or if this is the best expression to use

=(TimeSpan.FromMinutes(Avg(DateDiff(“n”,<Fields!Admission_Date.Value>,<Fields!Actual_Discharge_Date.Value>)))).Days
 “d “ &
(TimeSpan.FromMinutes(Avg(DateDiff(“n”,<Fields!Admission_Date.Value>,<Fields!Actual_Discharge_Date.Value>)))).Hours
 “h “ &
(TimeSpan.FromMinutes(Avg(DateDiff(“n”,<Fields!Admission_Date.Value>,<Fields!Actual_Discharge_Date.Value>)))).Minutes
& “m “ ))))